There is a long-term quest in ophthalmic surgery to improve human vision by improving optical quality of the eye. It is usually taken for granted that the eye is just another optical instrument, and that perfect vision requires a perfect projection of the image on the retina. To achieve this goal, all optical elements of the eye (primarily the cornea and the lens) are believed to be as aberration-free as possible and should be combined to form an aberration-free imaging system. It is generally assumed that any aberration will degrade visual acuity and decrease contrast sensitivity, in addition to potentially creating other visual disturbances, such as glare and halos in certain situations.
Spherical aberrations in human population have been the subject of study. Optical components even in a young, healthy eye may have significant aberrations, but they are deemed to largely compensate each other in a young, healthy eye. Since the spherical aberration of the eye is generally deemed to be detrimental to the vision quality, optical aberrations of patient's cornea, particularly spherical aberrations, are sometimes corrected by implantation of an aspheric intraocular lens (“IOL”) with opposite spherical aberration.
Consequently, there are numerous patents and patent applications covering methods and devices for decreasing aberrations of the eye, such as the following: Norrby, Sverker et al: Methods Of Obtaining Ophthalmic Lenses Providing The Eye With Reduced Aberrations, US Patent Application Publication No. 20020105617; Tabernero, Juan et al: Intraocular Lens For Correcting Corneal Coma, US Patent Application Publication No. 20070093891; Norrby, Sverker et al: Methods Of Obtaining Ophthalmic Lenses Providing The Eye With Reduced Aberrations, US Patent Application Publication Nos. 20040088050; 20070121064; 20070258044; 20090036980; 20110082542 and 20120059463; Lai; Shui T.: Intrastromal Surgery Correcting Low Order And High Order Aberrations Of The Eye, US Patent Application Publication No. 20080039825; Weeber; Hendrik Albert, et al.: System, Ophthalmic Lens, And Method For Extending Depth Of Focus, US Patent Application Publication Nos. 20090210054 and 20130060330; Portnoy, V.: Adjustable Multifocal Intraocular Lens System, U.S. Pat. No. 8,287,593; and Marmo, J. C.: Corneal Onlays And Wavefront Aberration Correction To Enhance Vision, U.S. Pat. No. 7,585,075, each of which is incorporated herein by reference.
Some investigators also describe post-operative adjustment of either optical aberrations of the cornea or the implanted artificial lens, particularly their spherical aberration (“SA”) of the lens in order to decrease the overall aberration of the eye. This is usually achieved by introducing a controlled degree of asphericity that also, in addition to causing certain amount of SA, also increases the depth of focus of the lens. Such methods and devices are described in numerous patents and patent applications, such as: Sandstedt; Christian A., et al.: Using The Light Adjustable Lens (LAL) To Increase The Depth Of Focus By Inducing Targeted Amounts Of Asphericity, US Patent Application Publication No. 20130072591; Peyman, Gholam A.: Intrastromal Corneal Modification Via Laser, US Patent Application Publication No. 20010027314; Adjustable Ablatable Inlay, US Patent Applications Publication Nos. 0020138069 and 20020138070; and Ablatable Intracorneal Inlay With Predetermined Refractive Properties, US Patent Application Publication No. 20030093066; Smith, David J., et al.: Accommodating Intraocular Lens System Having Spherical Aberration Compensation And Method, U.S. Pat. No. 7,637,947; and McGinn J. T., et al.: Electro-Optic Lenses For Correction Of Higher Order Aberrations, U.S. Pat. No. 8,154,804, each of which are incorporated herein by reference.
Some inventors describe intraocular lenses that change optical properties by transfer of fluid within its optics, and can be potentially used even for adjustment of SA, although that goal is usually not explicitly stated. Such inventions are described e.g. in the following US patent applications and granted US patents: Shadduck, John H.: Adaptive Optic Lens And Method Of Making, US Patent Applications Publication Nos. 20040184158; 20060061729; 20070299487; 20130060331; and Intraocular Implant Devices, U.S. Pat. No. 8,048,155; Sacharoff; Alex, et al.: Non-Invasive Power Adjustable Intraocular Lens, US Patent Application Publication No. 20090281620; Shadduck, John H.: Adaptive Optic Lens And Method Of Making, U.S. Pat. No. 7,264,351; Shadduck, John H.: Adaptive Optic Lens System And Method Of Use, U.S. Pat. No. 7,278,739; Esch, Victor: Lens System And Method For Power Adjustment Using Externally Actuated Micropumps, U.S. Pat. No. 7,438,723; Esch, Victor: Methods Of Adjusting The Power Of An Intraocular Lens, U.S. Pat. No. 7,485,144; DeBoer, et al.: Accommodating Intraocular Lens, U.S. Pat. No. 8,715,345; Phillips, A. Accommodating Intraocular Lens, U.S. Pat. Nos. 7,601,169 and 8,500,806; Boyd, et al.: Intraocular Accommodating Lens And Method Of Use, U.S. Pat. No. 8,167,941; Sean McCafferty, Accommodating Fluidic IOL With Flexible Interior Membrane, US Patent Application Publication No. 20140257478 and Refocusable Intraocular Lens With Flexible Aspheric Surface US Patent Application Publication No. 20140257479, each of which are incorporated herein by reference.
Change of the optical properties of the natural (e.g., human cornea) or an artificial lens by changing refractive index of their material are also described in numerous papers, patents and patent applications, such as: Phillips, A. J., System and Method for Treatment of Hyperopia and Myopia, U.S. Pat. No. 6,102,906, Bille J. F.: System For Forming And Modifying Lenses And Lenses Formed Thereby, U.S. Pat. Nos. 8,292,952; 8,920,690; 9,192,292; Sahler; Ruth et al.: “Hydrophilicity alteration system and method” U.S. Pat. Nos. 9,023,257; 9,186,242 and 9,107,746; Sahler; Ruth et al.: “intraocular lens (IOL) fabrication system and method” US Patent Application Publication No. 20160074967; Smith, T. et al.: Optical Hydrogel Material With Photosensitizer And Method For Modifying The Refractive Index, US Patent Application Publication Nos. 20130268072; 20090287306 and U.S. Pat. No. 8,901,190; Knox, Wayne H. et al.: Optical Material And Method For Modifying The Refractive Index, U.S. Pat. Nos. 8,932,352; 8,337,553; 7,789,910 B2; Knox, Wayne H. et al.: Optical Material And Method For Modifying The Refractive Index, US Patent Applications Publication Nos. 20130138093; 20130178934; 20100298933; 20080001320; 20090143858; 20090143858; Knox, Wayne H. et al.: Method For Modifying The Refractive Index Of An Optical Material And Resulting Optical Vision Component, US Patent Application Publication No. 20120310340, Knox, Wayne H. et al.: Method For Modifying Refractive Index Of Ocular Tissues, U.S. Pat. Nos. 8,486,055; 8,512,320; 8,617,147 and US Patent Application Publication Nos. 20110071509; 20130226162 and 20140107632; Knox, Wayne H. et al.: Method For Modifying Refractive Index Of Ocular Tissues And Applications Thereof, US Patent Application Publication No. 20120310223, each of which is incorporated herein by reference.
Spherical aberration can be also changed by implantation of an aspheric lens with conic optical surfaces, such as those described in the following patents and patent applications: Stoy, V. et al.: Bioanalogic Intraocular Lens, International Patent Application Publication No. WO2014111769; Wichterle, O.: Method Of Molding An Intraocular Lens, U.S. Pat. No. 4,846,832; Wichterle, O.: Soft And Elastic Intracameral Lens And Method For Manufacturing Thereof, U.S. Pat. No. 4,846,832; Stoy, V.: Implantable Ophthalmic Lens, A Method Of Manufacturing Same And A Mold For Carrying Out Said Method, U.S. Pat. No. 5,674,283; Sulc, J., et al.: Soft Intracameral Lens, U.S. Pat. Nos. 4,994,083 and 4,955,903; Blake, et al.: Aspheric soft lens, U.S. Pat. No. 7,192,444; Blake, et al.: Method Of Making Aspheric Soft Lens, U.S. Pat. No. 6,007,747; Hong, et al.: Intraocular Lens, U.S. Pat. No. 7,350,916; Hong, et al.: Aspheric Toric Intraocular Lens, U.S. Pat. No. 8,167,940; Hong, et al.: Optimal Intraocular Lens Shape Factor For Human Eyes, US Patent Application No. 20060227286; Portnoy, A.: Contra-Aspheric Toric Ophthalmic Lens, U.S. Pat. No. 8,668,333; and Michalek, J. et al.: Method Of Manufacturing An Implantable Intraocular Planar/Convex, Biconvex, Planar/Concave Or Convex/Concave Lens And A Lens Made Using This Method, U.S. Pat. No. 8,409,481, each of which is incorporated herein by reference.
The relation between the optical parameters of the eye and visual perception has been widely studied. The results show that individual optical components have significant aberrations, but they are deemed to largely compensate each other in a young, healthy eye. However, much of this relation is hitherto unexplained satisfactorily.